public class Test {
    public static void main(String[] args) {
        String s="abcdef";
        char[] c=new char[s.length()];
        for (int i = 0; i < s.length(); i++) {
            c[i]=s.charAt(i);
        }
        for (int i = 0; i < c.length; i++) {
            System.out.println(c[i]);
        }
    }
    public static void main10(String[] args) {
        String s="abcdef";
        System.out.println(s.substring(2));
        String s1="   sg dfd df  ";
        System.out.println(s1);
        System.out.println(s1.trim());
    }
    public static void main9(String[] args) {
        String s="hello world abc";
        String[] s1=s.split(" ");
        for (int i = 0; i < s1.length; i++) {
            System.out.println(s1[i]);
        }
        String s2="abc=de//gg=fgh.ij";
        String[] s3=s2.split("=|//|\\.");
        for (int i = 0; i < s3.length; i++) {
            System.out.println(s3[i]);
        }
    }
    public static void main8(String[] args) {
        String s="ababcabcd";
        System.out.println(s.replace('a','k'));
        System.out.println(s.replace("ab","ooo"));
        System.out.println(s.replaceAll("a","b"));
        System.out.println(s.replaceFirst("a","x"));
    }
    public static void main7(String[] args) {
        String s="abcdef";
        for (int i = 0; i < s.length(); i++) {
            System.out.println(s.charAt(i));

        }
        char[] c=s.toCharArray();
        for (int i = 0; i < c.length; i++) {
            System.out.println(c[i]);
        }
        String b=new String(c);
        System.out.println(b);
        String s1=String.format("%d-%d-%d",10,20,30);
        System.out.println(s1);
    }
    public static void main6(String[] args) {
        int a=Integer.parseInt("1234");
        double b=Double.parseDouble("12.3");
        String s=String.valueOf(10);
        System.out.println(s);
        System.out.println(a);
        System.out.println(b);
    }
    public static void main5(String[] args) {
        String s1="hello";
        String s2=new String("world");
        char[] value={'a','b','c'};
        String s3=new String(value);
        System.out.println(s1);
        System.out.println(s2);
        System.out.println(s3);
    }
    public static void main3(String[] args) {
        String s="hello";

    }
    public static void main4(String[] args) {

        String s="hello";
        System.out.println(s.toUpperCase());
    }
    public static String func(String s){
        String s1=s.toUpperCase();
        return s1;
    }
    public static void main1(String[] args) {
        String s="hello world abc";
        String[] s2=s.split(" ");
        s.toLowerCase();
        System.out.println(s.toUpperCase());
        for (int i = 0; i < s2.length; i++) {
            System.out.println(s2[i]);
        }
    }
}
